1. Field of the Invention
The present invention relates to an automatic flexible spacer and/or sealant applicator for glass work pieces and a method of applying the same, more particularly the present invention relates to a horizontal automatic flexible spacer and/or sealant applicator for a glass work piece that applies the flexible spacer and/or sealant along a single axis, and an associated method.
2. Background Information
The fabrication of insulated glass assemblies, also known as IG, requires the application of a spacer and sealant between the multiple glass panes. The spacer is typically placed a predetermined offset from the work piece edge and is placed around the entire perimeter of the work piece. A sealant may be provided around the perimeter in the offset between the spacer and the glass work piece edge. The purpose, function and relative position of spacers and sealants is well known in IG fabrication.
One well known spacer application method for IG fabrication is manual application of the spacer. The manual application of the spacer product generally requires skilled operators for effective throughput. The operators handle the glass, possibly contaminating the IG, creating part defects. The output capacity of the manual application process largely varies depending on the skill of the operator. The skill of the operator can also vary greatly from day to day and even throughout a given shift. Combining the operator quality variance with the fact that application process is already the IG fabrication line's bottleneck, creates an inconsistent production schedule. One attempt to provide an inexpensive solution was the Accuglyde™ manual spacer applicator table sold by Billco, and generally described in U.S. Pat. No. 6,030,475, which is incorporated herein by reference. This table provided a spacer application head movable along a single track axis, wherein a mechanical linkage would rotate the glass work piece on an appropriately spaced turntable, to maintain the glass work piece in the plane of the applicator head through the work piece corners. Although this table increased the quality of each IG fabrication, it was limited to the particular size of work piece associated with the linkage, and required appropriate centering of the work piece for accurate operation. Automated spacer applicators eliminate many of these issues.
There have been automated spacer applicators that have been developed, for example, Lisec offers a fully automated vertical line to perform IG assembly using SuperSpacer™ flexible spacer product. This complete line is quite expensive and not practical for many shops. Further, GED makes spacer applicator equipment for the aluminum Intercept™ spacer. This equipment, however, requires a large labor force to support the operation. Also, Besten provides an automated line for the Truseal™ line of warm edge spacers.
One drawback to the existing automated spacer applicator solutions is the complexity of the machine increases the initial cost and the maintenance required. In these existing applications an applicator head is configured to follow the edge of a glass work piece and must be indexed around the work piece. In horizontal applications, this creates significant difficulties with where to position the stock spacer material being supplied, which typically is supplied from a long roll that is paid out. One solution is to mount the spacer supply roll above the table on the carriage, but this makes roll changes to be difficult (as a roll of spacer material can weigh over 100 lbs). An alternative known solution is for mounting the roll adjacent the table, yet this leads to a great varying length of spacer material and associated complex pay out and tensioning rolls to lead from the supply roll to the distant carriage, and increases complexity and spacer losses with the end of each roll.
Additionally relevant prior art is disclosed in U.S. Pat. No. 5,013,377 that discloses a hand held spacer applicator device. The device is adapted to move on a support table and to generally remain in an upright position but the proper application of the sealant strip requires skill and attention. U.S. Pat. No. 5,246,331 discloses an air flotation assembly table that allows a sheet of glass to be conveniently moved and aligned toward a front working area. However, the application of the spacer, or strip, along the edges of a sheet of glass still requires skill and attention for the strip be properly positioned and aligned. If not done properly, the strip might be positioned inwardly from the edge in some locations and would be unacceptable if it appears uneven at the edge of the framing material after assembly. There is particularly concern during the application of the strip at the corners to insure that the strip is applied at a tight right angle. If not, the strip will be clearly seen after assembly.
U.S. Pat. No. 5,433,818 discloses apparatus for turning a glass work piece and for applying a sealing strip continuously along its edges. The apparatus includes an air flotation support bed covered by an air-permeable mat, a sealing strip applicator in a carriage, suction cup assemblies mounted for movement on respective mutually perpendicular slides for gripping the sheet at two adjacent corners thereof. The movement of the assemblies is coordinated such that, while gripping the sheet, one assembly is moved towards the initial position of the other assembly and simultaneously the latter is moved towards the corner diagonally opposite that at which the first assembly was initially disposed.
In addition, 3M is the assignee of U.S. Pat. No. 6,846,378 entitled “Tape applicator and methods of applying tape to a surface” which also relates to U.S. Pat. Nos. 6,793,758, 6,634,401 and 6,571,849. Cardinal is the assignee of U.S. Pat. No. 6,793,971 entitled “Methods and devices for manufacturing insulating glass units.” EdgeSeal is the assignee of U.S. Pat. No. 6,068,720 entitled “Method of manufacturing insulating glass units.”
Lafond is the assignee of U.S. Pat. No. 6,378,586 (entitled “Apparatus for automated application of spacer material for window assembly”); U.S. Pat. No. 6,329,030 (entitled “Composite insulated glass assembly and method of forming same”); U.S. Pat. No. 6,279,292 (entitled “Insulated glass window spacer and method for making window spacer”); U.S. Pat. No. 6,148,890 (entitled “Apparatus for the automated application of spacer material and method of using same”); U.S. Pat. No. 5,975,181 (entitled “Strip applying hand tool with corner forming apparatus”); and U.S. Pat. No. 5,888,341 (entitled “Apparatus for the automated application of spacer material”). Lenhardt is the assignee of U.S. Pat. No. 6,609,611 entitled “Device for conveying insulating glass panes”; U.S. Pat. No. 5,319,186 entitled “Apparatus for controlling the movement of a tool along the edge of glass panes”; and U.S. Pat. No. 4,561,929 entitled “Apparatus for applying an adhesive strip of plastic to a glass pane”.
Lisec is the assignee of U.S. Pat. No. 4,434,024 entitled “Device for assembling insulating glass panes”; U.S. Pat. No. 5,823,732 entitled “Device for moving insulating glass panes”; U.S. Pat. No. 5,394,725 entitled “Apparatus for the production of spacer frames for insulating glass panes from hollow profile strips”; a U.S. Pat. No. 5,173,148 entitled “Installation for the production of insulating glass”; U.S. Pat. No. 4,961,816 entitled “Apparatus for emplacing spacers”; U.S. Pat. No. 4,961,270 entitled “Apparatus for determining the spacing between glass sheets of insulating glass panes”; U.S. Pat. No. 4,885,926 entitled “Apparatus for the production of spacer frames”; U.S. Pat. No. 4,769,105 entitled “Device for the mounting of flexible spacers”; and U.S. Pat. No. 4,743,336 entitled “Device for mounting flexible spacers on glass sheets.”
Lockformer Company is the assignee of U.S. Pat. No. 6,038,825 entitled “Insulated glass window spacer and method for making window spacer.” Manser is the assignee of U.S. Pat. No. 5,932,062 entitled “Automated sealant applicator.” PPG is the assignee of U.S. Pat. No. 6,470,561 entitled “Spacer and spacer frame for an insulating glazing unit and method of making same” {which also relates to U.S. Pat. Nos. 5,501,013 and 5,351,451}; and U.S. Pat. No. 6,223,414 entitled “Method of making an insulating unit having a low thermal conducting spacer.”
Tremco is the assignee of U.S. Pat. No. RE35,291 entitled “Apparatus for laying strip on glass or like material”; U.S. Pat. No. 5,045,146 entitled “Tape applicator with corner forming device”; and U.S. Pat. No. 5,013,377 entitled “Apparatus for laying strip on glass or like material.” Weather Shield Mfg is the assignee of U.S. Pat. No. 5,640,828 entitled “Spacer for an insulated window panel assembly.”
The aforementioned patents are incorporated herein by reference and disclose the details of IG fabrication, sealant and spacer construction, sealant application head construction. There remains a need for an automated, horizontal spacer and/or sealant applicator for IG fabrication of minimal complexity.